Integrated
Circuits

1958:
Invention of the Integrated Circuit

Texas Instruments' first IC

As with many inventions, two people had the idea for an integrated
circuit at almost the same time. Transistors had become commonplace
in everything from radios to phones to computers, and now manufacturers
wanted something even better. Sure, transistors were smaller than
vacuum tubes, but for some of the newest electronics, they weren't
small enough.

But there was a limit on how small you could make each transistor,
since after it was made it had to be connected to wires and other
electronics. The transistors were already at the limit of what steady
hands and tiny tweezers could handle. So, scientists wanted to make
a whole circuit -- the transistors, the wires, everything else they
needed -- in a single blow. If they could create a miniature circuit
in just one step, all the parts could be made much smaller.

One day in late July, Jack Kilby was sitting alone at Texas Instruments.
He had been hired only a couple of months earlier and so he wasn't
able to take vacation time when practically everyone else did. The
halls were deserted, and he had lots of time to think. It suddenly
occurred to him that all parts of a circuit, not just the transistor,
could be made out of silicon. At the time, nobody was making capacitors
or resistors out of semiconductors. If it could be done then the entire
circuit could be built out of a single crystal -- making it smaller
and much easier to produce. Kilby's boss liked the idea, and told
him to get to work. By September 12, Kilby had built a working model,
and on February 6, Texas Instruments filed a patent. Their first "Solid
Circuit" the size of a pencil point, was shown off for the first time
in March.

But over in California, another man had similar ideas. In January
of 1959, Robert Noyce was working at the small Fairchild Semiconductor
startup company. He also realized a whole circuit could be made on
a single chip. While Kilby had hammered out the details of making
individual components, Noyce thought of a much better way to connect
the parts. That spring, Fairchild began a push to build what they
called "unitary circuits" and they also applied for a patent on the
idea. Knowing that TI had already filed a patent on something similar,
Fairchild wrote out a highly detailed application, hoping that it
wouldn't infringe on TI 's similar device.

All that detail paid off. On April 25, 1961, the patent office awarded
the first patent for an integrated circuit to Robert Noyce while Kilby's
application was still being analyzed. Today, both men are acknowledged
as having independently conceived of the idea.